考虑到开发人员有时候不小心误更新数据,要求线上库的 MySQL 实例都设置 sql_safe_updates=1 来避免没有索引的 update.delete. 结果有一天开发发现下面的一个SQL 没法正确执行: update t1 set col2=1 where key1 in (select col2 from t2 where key2='ABcD'); 错误如下: ERROR 1175 (HY000): You are using safe update mode and you tr
Of course, like any technology MongoDB has its strengths and weaknesses. MongoDB is designed for OLTP workloads. It can do complex queries, but it’s not necessarily the best fit for reporting-style workloads. Or if you need complex transactions, it’s
让Asp.Net WebAPI支持OData后,就能支持在url中直接输入排序,过滤条件了. 一.创建Asp.Net WebAPI项目: 二.使用NuGet安装Asp.Net WebAPI 2.2和OData包 三.修改WebAPIConfig.cs: using System; using System.Collections.Generic; using System.Linq; using System.Web.Http; using System.Net.Http.Formatting;
org.springframework.jdbc.BadSqlGrammarException: PreparedStatementCallback; bad SQL grammar [ SELECT * FROM `AAAA` Z LEFT JOIN (SELECT * FROM `BBBB` where targetdate >= ) M ON Z.TargetDate = M.TargetDate...]; nested exception is com.mysql.jdbc.except